Escaping $ references in OQL commands

[bsfarrell]

This is more or less a duplicate of #113, but for the more general case of any query that contains a ${...}.

For example, I want to show the sum of some LongAdder objects. Here's the best query I have been able to come up with:

SELECT 
  adder.base AS base, 
  (SELECT cell.value AS value FROM OBJECTS ${adder}.cells[0:-1] cell ) AS cells 
FROM java.util.concurrent.atomic.LongAdder adder 

Which gives results

           base |cells
----------------------------------------------------------------------------------
     14,651,647 |ObjectResultSet@5411f1c0[2][1][{value=23699102},{value=11644251}]
 Total: 1 entry |
----------------------------------------------------------------------------------

I can export this as CSV and post-process it with a script to add up the base and cells values, so this is sufficient for my purposes. (If there's a better query, please let me know!)

Then problem occurs when I want to run this query via the ParseHeapDump script. Regardless of whether I specify the query on the command line along with org.eclipse.mat.api:query, or if I create a custom report XML like the one mentioned in #113, I still get an error because the ${adder} string is removed. I can't seem to find any way to escape it.